Wire recording storage mechanism for bookkeeping machines



J. WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES L. STERLING Sept. 15, 1953 Filed May 20, 1949 16 Sheets-Sheet 1 INVENTOR.

' JOHN L. STEEZ/IVG UZZJAMU Sept. 15, 1953 J. L. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20 1949 16 Sheets-Sheet 2 @MQW Sept. 15, 1953 m J. L. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES 16 Sheets-Sheet 5 Filed May 20 1949 MOE I r 1 I $73 MHUEE xx J E v 3% m 3 m? wt kg ELK p 2 J. L. STERLING 2,652,196

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20 1949 l6 Sheets-Sheet 4 L. STERLING WIRE RECORDING STORAGE MECHANISM Sept. 15, 1953 FOR BOOKKEEPING MACHINES l6 Sheets-Sheet 5 Filed May 20 1949 Sept. 15, 1953 J. L. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES 16 Sheets-Sheet 6 Filed May 20 1949 T N E5 'Y W 4 m M Y B QUE P 1953 J. L STERLING 2,652,196

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 Sheets-Sheet 7 "INVENTOR. FIGIB JO/l/VZ. STEEL/N6 Sle t. 15, 1953 Filed May 20, 1949 I J. L. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES 16 Sheets-Sheet 8 'FIG. IOA

FIGIIA l\ 546 In 5 INVENTOR.

JOHN A. STE/E'l/A/G grime/v5) Sept. 15, 1953 V J. L. STERLING 2,652,196

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 Sheets-Sheet 9 FIG, l5 R 5 211 FIG. l6 l vii EEEEEIZEEE 7 JNVENTOR. JOHN L $7'EEL/N6 mmi/+42% Sept. 15, 1953 J. L. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES l6 Sheets-Sheet 10 Filed May 20, 1949 m T m V w w. 3 5 w 7/ .9 wa M310 04 M544 H E B R u mam E 3 W028 n H m mm 1 W H W Y M w N n w An N w W s M II I O I O mw VK D N u 0 Q C 8 R 2 0.? i

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Sept. 15, 1953 J. L. STERLING 2,652,196

7 WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 sheeis-sheei 11 K 'INVENTOR.

Joy/v Z. 'J/z'ez/AM 4 r rael'wrr Sept. 15, 1953 J. L. STERLING 2,652,195

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 Sheets-Sheet 12 JNVENTOR. JOH/V 4. STE/Q4 0V? Sept. 15, 1953 J. L. STERLING 2,652,195

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 Sheets-Sheet 13 INVENTOR. Jaw/v z. 575/24 0v;

mamzfm Sept. 15, 1953 J. 1.. STERLING WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES l6 Sheets-Sheet 14 Filed May 20, 1949 Mmrwroe JOHN z. 575/?! //V6 Sept. 15, 1953 J. L. STERLING 2,652,195

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES v Filed May 20, 1949 16 Sheets-Sheet 15 INVEN TOR. JOHN L Siren/m Sept. 15, 1953 J. STERLING 2,652,195

WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES Filed May 20, 1949 16 Sheets-Sheet 16 IN VEN TOR. Jo/ml 4 JIZRZ ING Patented Sept. 1 5 1953 WIRE RECORDING STORAGE MECHANISM FOR BOOKKEEPING MACHINES John L. Sterling, Bellerose, N. Y., assignor to Remington Rand Inc., New York, N. Y., a corporation of Delaware Application May 20, 1949, Serial No. 94,324

24 Claims. (Cl. 23561.9)

This invention relates to business machines, and more particularly to an accounting machine in which a plurality of balances may be stored, selectively entered into an accumulator, amounts subtracted and added to said balance, and the new balance returned to the storage mechanism.

In the past balances have been entered on ledger sheets in a manner permitting them to be sensed and picked up later to actuate an accumulator, thus obviating the necessity of the operator copying the old balance and possibly. making an error. Another system entailed the punching of the balance in a separate card which was attached to the ledger and later sensed to enter the old balance. Often the card was misplaced which required that the old balance be copied in by the operator.

It is the principal object of the invention to provide a storage mechanism for old balances in which the amounts are entered by magnetic impulses in a tape or the like, which balances may be selectively withdrawn and entered in an accumulator without intervention of the operator.

Another object is to provide electrical circuits over which balances read out of an accumulator may be entered in the form of magnetic impulses in a tape or the like, without intervention of the operator.

A further object of the invention is to provide a selecting mechanism whereby a desired balance may be selected from a plurality of balances under control of a sensing mechanism.

A still further object is to provide a sensing mechanism which will be actuated by data in a ledger sheet, and control a selecting mechanism for selecting the balance corresponding to that data.

Another object is to provide a device whereby any one of a plurality of balances recorded in a tape or the like by magnetic impulses may be selected and read out into an accumulator.

Another object is to provide electrical circuits for controlling the selection of any one of a plurality of balances recorded by magnetic impulses in a wire or tape, reading said balance and entering it into an accumulator.

A still further object is to provide an accounting machine in which an amount recorded in a magnetic tape or wire is automatically read out into the machine, and a new amount automatically read out of the machine and re-recorded in the tape.

A feature of the invention comprises a plurality of tapes wound on drums each tape capable of being magnetized by magnetic impulses to represent a balance in a particular account.

Another feature is the provision of a sensing mechanism for sensing an account number from a ledger sheet or the like, which sensing mechanism controls electrical circuits which, in turn, control a travelling carriage for selecting the particular tape containing the balance of the desired account.

A further feature is the electrical circuits whereby the magnetic impulses in the selected tape are caused to set one or more accumulators to the amount standing in the tape and print the same amount.

A still further feature is the electrical circuits whereby an amount standing in the accumulators of a bookkeeping machine is entered as magnetic impulses into a tape.

The preferred form of the invention comprises a plurality of tapes wound on drums carried on rotating shafts, which tapes are capable of being magnetized by impulses from a cross totalizer. Each drum contains a balance which has been previously entered and may be selected by a carriage carrying a reading and recording head. The selecting carriage is under control of a sensing mechanism which senses the number of the desired account from perforations in a ledger sheet carrying the past transactions. Upon selection the balance is read out of the tape by the reading head and entered in an accumulator and cross totalizer. Any number of transactions may then be entered in the machine manually, and a new balance obtained. This new balance is then read out of the cross totalizer and recorded through the recording head as magnetic impulses in the tape.

The recording of data by magnetic impulse on a tape or wire is taught by the patent to V. Poulsen 661,619 November 13, 1900, and many others. The bookkeeping machine disclosed in the drawings is similar to that disclosed and described in the patents to E. O. Roggenstein 2,364,758, December 12, 1944, F. W. Schremp 2,288,846, July '7, 1942, and Dodge et al. 2,064,154, December 15, 1936.

A more clear conception of the operation, construction, and further objects of the invention may be had from the following specification when read in the light of the accompanying drawing, in which Fig. 1 is an isometric view of the invention showing the bookkeeping machine and storage unit;

Fig. 1A is a detail showing of the magnetic storage elements;

Fig. 2 is a cross section through the midsection of a bookkeeping machine;

Fig. 3 is an enlarged partial front view of the totalizers of the bookkeeping machine;

Fig. 4 is a detail side view of the vertical and cross totalizers and some of the sensing mechanism for total read out;

Fig. 5 is an enlarged view of the total read out mechanism;

Fig. 6 is a partial cross section taken along line 6-43 of Fig. 5 showing some of the mechanism in the cross totalizer;

Fig. 7 is an enlarged section showing the action of the sensing teeth with the cross totalizer wheels;

Fig. 8 is a front elevation of the balance storage mechanism;

Fig. 9 is a cross section taken along line 9-9 of Fig. 8;

Figs. 10 and 10A combined form a plan view of a portion of the magnetic tapes and the selecting carriage in the magnetic storage device;

Figs. 11 and 11A combined form a front elevation of Figs. 10 and 10A;

Fig. 12 is a cross section taken along line iE-i 2 of Fig. 11 showing the reading and recording heads in the magnetic storage device;

Fig. 13 is a detail front view of a magnet coil as used in the magnetic reading or recording heads;

Fig. l l is a cross section taken along line M-M of Fig. 13;

Fig. 15 is a plan view of the sensing mechanism for controlling the account selecting carriage;

Fig. 16 is a cross section taken along line l*-% is of Fig. 15;

Fig. 17 is a vertical cross section taken along line [1-41 of Fig. 16;

Figs. 18, 19, 20, 21, 22, and 23 combined in accordance with Fig. 24 form a wiring diagram of the invention;

Fig. 24 is a schematic diagram for combining Figs. 18 to 23 inclusive;

Fig. 25 shows the construction of the commutators in the pulsing circuit for the magnetic disc selecting mechanism;

Fig. 26 shows the commutators in the pulsing circuit for the balance read out device;

Fig. 27 shows the commutators for controlling a rotary switch and impulses to the print solenoids;

Fig. 28 is a detail view of thesolenoid for controlling the ledger card sensing pin mechanism for account selection;

Fig. 29 is a schematic diagram-of'the operating circuit for the ledger card sensing mechanism; and

Fig. 30 is a fragmentaryview of aledger sheet and a statement.

The invention resides in the combination of a bookkeeping machine on which bills, statements and the like may be made with a magnetic storage device wherein old balances may be stored. There is also provided a sensing 'meclianism whereby an account number punched in the ledger sheet on which the transactions are to be entered is sensed and the portion of themagnetic storage device containing the old balance in that account may be selected.

If, for example, a bankstatement is to be made out, as will be described in detail later, the particular ledger sheet for that account is inserted in the sensing mechanism and circuits are setup selecting the particular drum inthe storage unit which carries the present or old balance in that account. After the drumisseIctedthe-[ledger sheet and customers statement are placed on the platen of the bookkeeper and the carriage is positioned at its extreme right hand position or with the first vertical totalizer in the entering position. Ehe operator now actuates a reading and erasing, key for magnetic readout devices and a start key which activates all circuits. The old balance is read out of the previously selected drum and by actuating one of a set of ten numeric solenoids causes the old balance to be entered in the vertical totalizer located at that carriage position, into the cross footer and prints the amount on the statement and ledger. The magnetic storage device while still connected has no further function until the total is later read out. lhe car-- riage is then tabulated to align the debit or credit accumulator with the entering mechanism and the amount or amounts of the present transaction are entered by the keyboard.

All amounts entered additively in the vertical totalizers or accumulators are entered in the cross totalizer additively and vice versa. When the present transactions have been completed the carriage is tabulated to the total read out position. In this position the circuits to the magnetic storage are again effective and the new balance is transferred as magnetic spots onto the drum from which the old balance has been erased and printed on the ledger and statement. In order to clear the vertical totalizers in which the present transactions have been entered a reverse key is actuated causing all those totalizers, which were set to add, to now subtract and vice versa. The carriage is moved to the entering position and the same amounts entered thus clearing the totalizers and placing them in condition for the next statement. "The amount entered in the magnetic drum now becomes the old balance and remains until neededfor a future statement.

In Fig. l is shown the preferred form ofmachine comprising a plurality of banks of storage devices housed in a casing 10. A cable Hinterconnects the circuits in the storage devices and the bookkeeping machine l2, whichis similar in all respects to that described and disclosed in the patent to O. Roggenstein referred to above, and only those portions of the bookkeeping machine necessary to a complete understanding of the invention will be described. A sensing mechanism I3, for selecting a particular account is positioned alongside the beokkeeping machine and is connected to cable ll.

Referring to Fig. 2, the machine comprises an electrified typewriter, fragments of the frame M being shown. The typewriter carriage [5, which is power driven, supports a-platen Hi. The type bars I? are operated by sub-levers It. The sublevers which operate alphabetic type bars -are actuated by levers l9, and those which operate numerical type bars by levers-20, whichf together with the alphabetic key levers '21 and :the num rical key levers 22, are all pivotedcn an angle bar 23 at the rear of the machine. Ml of the type bars are operated by a power drive including three continuously rotating shafts, namely, a shaft 24 for actuating the computing mechanism and the numerical type bars, a snatch'roll-ZS for operating the alpha type bars, and a thirdfishaft 26 which operates the tabulating,backspacing, and carriage shift mechanisms. These three shafts are driven counterclockwise (Fig. :2) by any wellknown means, such as a motor.

Each of the alphabet type bar operating-levers l9 hasa hook--21 pivoted thereon and-hanging down in front of the snatch roll 25. Each of the alphabet key levers 2| has a depending'arm 28 adapted to rock a bell-crank 29 carrying ahook 30 engaging the upper portion of depending hook 2! in such fashion that when a key lever is depressed, the hook 2'! is swung into engagement with the snatch roll 25, thus depressing the lever 19 and operating its associated alpha type bar.

Mounted on shaft 24 is a series of cams 3!, one for each numeral key and type bar. Said cams are loose on the shaft and each has associated therewith a clutch, the dog 32 of which is adapted to engage a toothed wheel (not shown) fast on the shaft 24. The dog 32 is controlled by a latch 33 adapted to be tripped by a depending arm 34 pivoted to the associated numeral key lever 22, with the result that the dog 32 engages the toothed wheel and drives cam 31 for one revolution, at the end of which the dog is thrown out by engagement with the latch 33. Each cam controls a follower arm 35 urged downwardly by a strong spring 36. The shape of the cam is such that it rocks the follower 35 down andthen up to its normal position. Pivoted to the arm 35 is a pawl 37, which, when the armis at the bottom of its travel, snaps under the front end of a lever 38 pivoted at 39 and is connected at its rear end by a pin and slot connection to a'numeric type lever 20. On the up stroke of the arm 35, pawl 31 rocks the lever 38 which operates its associated type bar. Each arm 35 has pivoted thereto a link 40 which ispivoted to a lever 41 which is, in turn, connected to a vertical link 42 for operating a goose neck and sector gear 49 associated with the totalizer. This mechanism is well known and described in detail in the patent to Wahl, 1,270,471.

Associated with each latch and engaging a depending arm thereon is a solenoid I20 which is adapted to be operated normally by the totalizer read out mechanism or the magnetic drums of the present invention as will later be described.

The typewriter carriage has a feed rack '53 engaging a, pinion 44 connected with an escapement wheel 45, which is controlled by feed dogs mounted on a dog rocker 46, operated by a link 47 which, at its forward end, is pivoted at 48 to an arm 50 on a rock shaft 5|, which shaft has on its ends (hidden) two upright arms, to which are pivoted the extensions 52 of a universal bail 53 mounted in an are shaped frame in a type bar basket 54. The universal bail 53 is actuated by the heel of a type bar when thrown to the printing position. The dog rocker 36 may also be operated by a space bar 55 whose arms 56 are fast on a rock shaft 51 having an arm 58 articulated at 50 with a lever 6 l the upper end of which engages an ear 62 on the link 41.

The carriage is drawn to the left by the usual spring. This motion may be controlled on occasion by a tabulator mechanism. The stop bar 59 at the rear of the typewriter carriage carries column stop 63 adapted to be arrested by denominational stops 64 mounted in a frame 65 at the rear of the typewriter. The stops 34 are operated by vertical levers 66, which, in the present machine, are or may be operated by power under control of the tabulator keys 61 at the front of the machine. The mechanism for operating most of the denominational stops is not shown herein, but the drawing does show the mechanism for operating one of the stops 64 automatically by the travel of the typewriter carriage. Thls particular stop is operated by one of a plurality of levers 66, which, like the other suchlevers, is.

operated by a slide 68 which, in turn, is operated by a vertical lever 10 pivoted in a special tabulator frame II. 'This mechanism is substantially the same as that described in the patent to Dodge et al., 2,064,154, December 15, 1936, and it will, therefore, be unnecessary to describe it further. Lever 10 is operated by a link 12 pivoted on the follower lever 73 of a cam 74 which is loose on the drive shaft 26 and operated by a clutch comprising a toothed wheel fast on said shaft and engageable by a dog 15. This dog is normally held out of engagement by a compound latch 16 in the form of a three armed lever pivoted at T7, the horizontal arm of this lever normally holding the cam in the position shown in Fig. 2. When this lever is rocked counterclockwise to release the dog 15, a tooth or hook on the end of the upright arm 18 of this lever moves into the path of the dog 15, and arrests the dog at about the end of a quarter rotation of the cam, so that the cam stands in that position until the compound dog is rocked back to normal position. When that occurs the dog is released from the latch arm 18 and is, at the end of its complete rotation, arrested in normal position by the arm 16. The outline of the cam i4 is such that, during the first quarter rotation thereof, it rocks the follower lever 73 toward the rear, moving the stop 64 into active position and holding it there until near the end of the complete rotation of the cam. More than half of the outline of this cam is a concentric high part, so that the stop 64 is not withdrawn instantly on the release of the dog arm 13, but remains in stopping position until near the end of the rotation of the cam, thus giving the carriage time to settle down from any vibration that may have been caused by its arrest.

The latch or detent I6, is operated by a platelike elver 80, which lies beneath the rearwardly extending third arm of the latch member. This lever is adapted to be rocked clockwise in order to operate said latch by a long rod 8i resting on its rear end and extending upward to a point.

above the top plate of the typewriter, where its upper end rests under the end of an arm 82 of a device arranged to rock on a transverse horizontal pivotal axis, and comprising an upstanding arm 83 adapted to cooperate with a cam "59 mounted on the underside of the rack bar 43 in such manner that it can be set at any desired location lengthwise of said bar.

Except as hereinafter described, the computing mechanism is of the sort that has long been used in the Remington machine and which is described in a line of patents, which, in a way, may be said to begin with that to Wahl 1,270,471, dated June 25, 1918. The differential and control mechanism of this computer is mostly mounted on a casting 84 (Fig. 3), which casting is secured to the front of the top plate of the typewriter. Vertical totalizers or dummies 85 may be mounted at whatever points desired on a main truck 86, connected with the typewriter carriage M by means of certain arms 8'! having pin and slot connections with brackets 88 at the ends of the truck. The machine also includes a cross footing mechanism including a cross truck 9| carrying a cross totalizer 90 and picked up by the vertical totalizers 85 one after another through the intermediary of a. pick-up beam 92. At the end of each computing column the cross truck is freed from the vertical totalizer and is drawn back by a spring to its initial right hand position.

., The links 42 (Fig. 2), operate the usual fanf.

segments and goose neck cams 49,,which'rock a differential shaft 93 (Fig. 3) and. operate the vertical master wheel 94 (Fig. 4) and. a cross master wheel 95 to rotate the carrier gearwheels 96 and 9'! of the vertical and cross total izers, respectively. Motion of these gear wheels is transmitted by idler gears 98 (Fig. 5) to dials I09. The transfer mechanism, etc., are all of the usual kind. The vertical master wheel is reversible for subtraction by means of the usual hand lever, not shown which lever is used during clearing operations. The cross master wheel. is reversible for subtraction by, the usual means including a follower roller IIlI (Figs. 3 and 4) mounted on an arm I02 fast on a rock shaft tilt and operating the reversing mechanism. The follower roller Iill is under the control or cam plates I04, one on each of the vertical: totalizers 35, and each cam is settable to an upper position where it does not depress the roller IIH but leaves the cross master wheel set for addition, as in the first two (OB and CR) of the five totalizers shown in Fig. 3, or to an intermediate position as in the fourth totalizer ST shown, where it disconnects the cross master wheel leaving it inoperative, or to a lowest position shown on the third and fifth totalizers CR and T, where it depresses the roller IIlI to the full extent and sets the-cross master wheel for subtraction. The totalizers 013, ST, and T are dummies in that they do not register but merely control the cross totalizer by their cams. Both the vertical and cross master wheels may be reversed simultaneously, each irrespective of whether set originally for addition or subtraction, by a mechanism described and shown in the above Roggenstein patent. This mechanism is controlled by the correction key 99 (Fig. l) and may be set manually or. by. an impulse from the magnetic storage tape or the total read out mechanism, as will bedescribed later.

Total read out mechanism (Figs. 4, 5, 6)

The cross totalizer 90 is provided with an extra shaft I05 having journaled thereon a set of thirty-toothed wheels I66, one meshing-with each of the carrier Wheels 91. Each of the wheels I06 has riveted thereto a spacer I01 and a disc I08. Each disc I08 has three teeth IDS-project'- ing therefrom and capable of being sensed so as to read the indication of the wheel. The totalizer has one carrier wheel at its extreme left hand side not connected with a dial, but provided with a special disc H having fifteen teeth H3, cooperating with sensing finger I2"I (Fig. for indicating a positive or negative balance.

The sensing unit for reading the cross totalizer comprises a framework carrying a piece of insulating material HI an arch or segment of a cylinder, whose end is secured to plate H2 by screws. The right: hand end of this segment is supported by a frame member H4 (Figs. 5 and 6) secured to rods H5;

The means for sensing the digital positions of the totalizer wheel consists essentially of aseries of ten sensing fingers I [1 adapted to make electrical contact with the teeth I09. These fingers have their ends projecting intothe paths of movement of the teeth I09 as the latter travel with the carriage.

said arc, thev same. as the teeth. of the wheels I06, and are so situated that whenin the leftward. travel of the carriage a. particular carrier wheel 91 is inv mesh with the master wheel 9.5,.

one of the teeth I09 of its meshing wheel. I06

(Fig. 4) in the shape of They are'arranged in an arc about the shaft I05 and are spaced 12 apart in is in. contact with-a-finger III, as shown in dotted lines inFig. 7.

Each finger H1 is pivoted to a support H8 which isitself pivoted to a fixed but adjustable plate H9, secured to a post H6 which passes through and is supported by the arched insulator III. A spring is compressed between the plate H9 and a branch of the finger III tending to rock said finger clockwise about. its pivot, such rocking being limited by a pin on the support H8. The construction is such that the finger has a fixed rest position relative to the supportand is free to swing leftward but not rightward.

The right hand edge of the tooth I09 and the left hand edge of the finger II'I are leveled so that, when the tooth is travelling with the carriage toward the right, it. cams the finger. out of its path. As the finger III cannot swing rightward about. its own pivot, the support H8 swings clockwise, so that the finger is swung out of the path of the tooth and snaps in'behind it after a relatively short travel of the carriage, as will be apparent from. Fig. 7. On the other hand, as the carriage steps leftward the construction is such that the tooth is in contact with the finger through a materially greater extent of the travel of the former beforeit moves out of its path and snaps back. A tooth Iflflris shown by solid lines one step to the right of its active position. It

will be. seen that the tooth, when being carriedleftward to its active position. (shown in dotted lines), makes contact a little before reaching the rest position and does not lose contact until after moving a considerable part of the next succeeding step, alsoshown in dotted lines. This isimportant, as the escapement and'the-tabulator stops which arrest the carriage are at the rear of the machine on the carriage and the totalizer is at the front, and when thecarriage-is arrested there is a certain amount of overthrow of the totalizer, which vibrates back and forth for a moment and to some extent, which, except for the above construction, might cause the tooth to lose contact with the sensing finger.

The post H61 passes through a threaded sleeve IZI (Fig. 7) having a washer I22. and a nut I23, a conductor wire being soldered to the washer. Each plate H9 hasa sheet of insulation secured to one face thereof to avoid contact with adjacent. plates; I [l are insulated from the frame of the machine and from one another, so that a circuit may be established from a tooth I08. to actuate a print solenoid I20 which rocks the latch 33 (Fig. 2) to actuate a numeric print. bar I-I which prints the number and enters the amount in the vertical totalizer, as described above.

The normal position of a finger II'I. (Fig. '7) is just to the right of. the rest position of a tooth I09, so that said fingersdo not interfere with the rotation of the totalizer wheel. When the amount is entered as above, it is subtracted'from the. totalizer, causing the register wheel to be turned to zero. This rotation moves the tooth out of contact with the finger which immediately snaps to its normal position, where it is outof the way.

In order to detect. the arrival of the master wheel at a totalizer wheel which at the time registers a digit other than zero (significant digit), the followingmechanism is provided (Figs. 3, 4,, and '1). sensing fingers. III there ismounted a metallic arch shaped detector. I24. This detector is mountedonan armor lever I25 which is pivoted- It will be seen that allof the fingers Just at theright of the row of 

